The Scientific Core exists to facilitate the scientific projects within the program. The services, materials and reagents provided by the Scientific Core are purified scrapie prions, PrP antibodies, synthetic peptides and oligonucleotides, and an analytical service for peptides and proteins. This core will be directed by Dr Michael Baldwin, an analytical chemist of considerable experience who directed a core service laboratory in the University of London for 14 years and who has devoted himself to research into prion chemistry and biochemistry for the last 3 years. The preparation of purified prions has been carried out in this laboratory for more than a decade. In recent years this program has been supervised by Ms Hana Serban. She will oversee the work of a new SA II who will carry out the large-scale purifications required for projects III and V and for antibody production. PrP antibodies, crucial to the success of most of these projects, will be prepared and supplied by a second SRA II who will also synthesize peptides and oligonucleotides. Peptides are required for antibody production and for a variety of other purposes including binding studies, structural analysis and active site/infectivity experiments. Oligonucleotides will be needed for several projects as sequencing aids, for PCR, and in project IV for construction of cosmids for transgenic mouse production. People and protein analysis will also be carried out by the second SRAII. All of these activities are currently being carried out very successfully in this laboratory and there are highly experienced personnel who can train and advise the new staff. The appointment of new staff is essential to cope with the high volume of work that will be created by this program.